(3ChVGY GdYGde (B1987 /s - (3SGfOQG HhSJd,LhO LjcHShf,dSJQ Q(B. (3HQhGf s; (3TGgjf(B;(3SgGhfgs ((3HjQhJ (B:s (3eDSSI GdQSGdI ,s, 1987)
Keywords: (3GdEbJUGOs; (3OjeZQGajGs; (3GdHjFIs